Black hole: First picture of Milky Way monster

This is the gargantuan black hole that lives at the centre of our galaxy, pictured for the very first time.

Known as Sagittarius A*, the object is a staggering four million times the mass of our Sun.

– A black hole is a region of space where matter has collapsed in on itself

What is a black hole?

If you compare the new image to the previous one of M87, you may wonder what's different. But there are key distinctions.

The telescope observations for both black holes were actually acquired during the same period in early 2017, but M87, at its greater size and distance of 55 million light-years, looks static by comparison.

Scientists have already begun to deploy the measurements in the new image to test the physics we currently use to describe black holes. So far, what they see is entirely consistent with the equations set out by Einstein in his theory of gravity, of general relativity.

We've suspected for several decades that a supermassive black hole lives at the centre of the galaxy. What else could produce gravitational forces that accelerate nearby stars through space at speeds of up 24,000km/s (for comparison our Sun glides around the galaxy at a sedate 230km/s, or 140 miles per second)?

"Every time we get a new facility that can take a sharper image of the Universe, we do our best to train it on the galactic centre, and we inevitably learn something fantastic," said Jessica Lu, the professor from the University of California, Berkeley, US, who will lead the Webb campaign.

The EHT collaboration's results are being published in a special issue of The Astrophysical Journal Letters.